Figure 100. Students of an agricultural high school constructing a tile drain.

This is rather expensive, as the labor is considerable, and several tiles may be broken in the attempt to make the desired fitting. To insure a close joint, broken pieces of tile or stones may be laid or fitted about the rather crude opening.

Protecting the tiles from the roots of trees.-Where the line of drain tile passes under a willow hedge or near other trees the roots of which grow readily in wet ground, there is danger that the roots may enter between

the ends of the tiles and by branching within the drain close it up so as to stop the flow of water. Bunches of roots thus

the stake at each station, or only in the notes, measurement can formed within a

be made from the station to a given point above the proposed bottom for the drain, say 7 feet, and a small steel wire, "broom wire," can be stretched between the two stations parallel to the bottom of the ditch. It is then a simple matter to measure down

grade the bottom of the ditch with a tile hoe.

tile drain are

with an L-shaped measure set to determine the proper depth to shown in Figure 105. By using sewer tiles with shoulders, and closing the ends with cement, these roots may be kept out. This, of course, is not desired in land needing drainage, since the water could not penetrate into the tiles, and is only necessary to thus protect a length of several rods where a tile drain must carry its

water past trees.

Filling the ditch.-In some instances, the hand shovel is the most practical

Figure 102. Quiet water in a sag in a drain tile allows sediment to settle there and clog the drain.

tool to use in filling the tile ditch. The slush scraper, as shown in Figure 106, may be used to advantage. A chain, 10 or more feet long, is necessary that the team

may be backed up near to the ditch. Where the ground is solid, the eveners may be carried on the front wheels of a wagon, or better still, by means of the hind wheels of the wagon, supplied with a tongue. The hind wheels being larger can be backed up more easily.

man can sometimes do this work, but a second man is usually necessary to drive the team, at least until it is taught to turn and back at command. A specially

con

structed scraper, as shown in Figure 107, with a long tongue, can also be used in filling a ditch by having the team on the opposite side of the ditch from the ridge of excavated earth. Some reversible

road machines

One

are so built that drains, showing how a man can get down into a narrow ditch. they can be used

Figure 103. Agricultural high school students laying tile

to fill the ditch very cheaply, as shown in Figure 108. Before filling with team power, the tiles should be covered by a workman who fills in several inches of earth and treads it firmly about the tiles.

Opening the ditches with machinery.—In a previous paragraph, plowing out furrows with the common plow was advised; in some cases the capstan ditching plow can be used for throwing out the first 18 to 24 inches of earth, thus greatly lessening the amount of hand digging for tile drains.

Tile-ditching machines which throw the dirt to one side of the ditch have been invented, and some of them

Figure 104. Tile

hook, handle 7 feet

have been used with more or less success. Others have been devised to carry the dirt backward and throw it again in the ditch behind a man who lays the tiles; and still others which automatically lay the tiles have also been projected and made almost successful in soils which are free from stones and on which the machine can be run without sinking too deeply into soft earth.

The grade of the bottom of the tile is controlled, in case of machines for openlong, hook 10 inches ing the drain, by means of levels marked on stakes, above the line of the ditch, with cross bars at a given distance above the desired grade of the bottom of the drain, the operator on the machine keeping the depth of the ditching device under control by sighting from a point on the machine to these cross bars of the successive stakes. Figure 110 shows a mole tile-ditching machine with attachment. A, capstan; B, mole ditching machine; X, man controlling grade of the drain with a wheel and keeping the marker, mounted on the mole coulter in line with markers, O-P, on two stakes so placed as to be parallel with the line of the desired grade. A man sitting in a pit lays tiles on the steel ribbon, F, which is attached to the large steel mole, M, and they are drawn into place. These pits are placed every 50 or 100 feet. These

machines have not had extensive use.

Capstan mole ditching machines without tiles are also sometimes used in tough clay subsoils, in which the drain may remain open for some time.

Outlets and silt wells.-Outlets need to be carefully arranged, so that stock coming to the mouth of the drain

Figure 105. Masses of maple roots taken from 3-inch drain tiles.

to drink cannot disturb the ends of the tiles by tramping, and it is wise to place a wire screen over the opening, that rabbits and other small animals may be kept out of the drains. Stones laid at the outlet, or masonry built at this point, are sometimes necessary.